Digital media coming from a GoPro cam or others mostly do not provide timecode meta data. Use tcAgent to resync digital media for postproduction, with apps like FCP, Mediacomposer, Premiere Pro and others. Using tcAgent is straightforward. Open a .mov file, type a new starting timecode and save. Thats it. The timecode will be available instantly, there is no rendering process you have to wait for. Timecode can always be edited at any time with tcAgent.